This invention relates to a calender device for the production of calendered rubber asbestos sheets, particularly sealing sheets of the type known as "It sheets".
These sheets are made by applying a liquid or paste of asbestos fibers in rubber onto the heating roll of a calender system and thinning out the applied liquid or paste while vulcanizing it by suitable heating of the roll. The sheet then adheres strongly to the heating roll. In order to remove the sheet from this roll, it is necessary first to make a longitudinal cut in the vulcanized layer on the roll. Thereupon it has been necessary, thus far, to use at least two workers, each of whom had to manually grip an edge portion of the sheet, adjacent the cut, and then to manually draw the sheet from the roll. The workers had to stand in the direct vicinity of the hot calender roll. They had to manually grip and hold the equally hot, calendered sheet. Moreover the drawing off of the sheet had to be done in most cases in the forward rotational direction of the heating roll, at the relatively rapid velocity of this roll's rotation.
Very experienced workers were needed for this operation. Moreover their work was extremely fatiguing. Still further, it often was difficult for them to properly lift the sheet from the roll, particularly when the sheet was relatively thin; these conditions lead to dangers for the workers, who could not only suffer burns on their hands but could also be injured by having their hands caught by the rotating rolls; in addition the operation often was inefficient. Damaged and unusable plates were all too often produced.